Converse flexoelectricity with relative permittivity gradient

Abstract

Flexoelectricity represents the linear relationship between the strain/electric gradient field and the induced electric polarization/mechanical stress in dielectric materials. This electro-mechanical behavior is important for prospective applications due to its size effect and other advantages. In this work, a converse flexoelectric effect is generated by the designed permittivity gradient with Ba0.67Sr0.33TiO3 ceramic powder and the substrate. The equivalent piezoelectric effect of the gradient composite is obviously increased by converse flexoelectricity. This study opens up an avenue for prospective sensing and actuating approaches for both piezoelectric and non-piezoelectric dielectric materials with relative permittivity gradients and uniform geometric structures.